And the 45L variant is the biggest thing you can use as a carry-on.
https://www.peakdesign.com/products/travel-backpack?Size=45L...
I've never spent $300 on a backpack before. It kinda stung. It's well-thought-out though. I've had it five years and it's been through a lot.
The FAQ says to hand-wash it which is annoying though. There's no way you're gently washing out the sort of grime that my human oil leaves on the straps from real use, like clinging to your bare shoulders during a long sweaty trip through Mexico.
So I feel a lil mischievous tossing the thing into the washing machine every year. Same way I feel using an alcohol wipe on my Macbook screen.